Friday, March 20, 2009

The first day of spring is no guarantee of spring-like weather, but officially the season's start comes around at the same time each year nonetheless.

Well, sort of.

The first day of spring arrives on varying dates (from March 19-21) in different years for two reasons: Our year is not exactly an even number of days; and Earth's slightly noncircular orbit, plus the gravitational tug of the other planets, constantly changes our planet's orientation to the sun from year to year.

And weather-wise, Earth's seasons have shifted in the past 150 years or so, according to a study that came out last month.

The hottest and coldest days of the years now are occurring almost two days earlier.

This year, spring starts Friday, March 20, because that is when the so-called vernal equinox occurs. Equinoxes (which mark the onset of spring and autumn) and solstices (which mark when summer and winter begin) are points in time and space that mark a transition in our planet's annual trip around the sun.

At each equinox, the sun crosses the Earth's equator, making night and day of approximately equal length on most of the planet. At the equator, the sun is directly overhead at noon on either equinox.

How it works

Earth's multiple motions — spinning on its axis and orbiting the sun — are behind everything from day and night to the changing seasons.

The sun comes up each day because Earth rotates once on its axis every 24 hours or so. Seasons are a result of Earth being tilted 23.5 degrees on its spin axis coupled with the planet's 365-day orbit around the sun.

(At the North Pole, the sun rises only once a year — at the start of spring. It gets higher in the sky each day until the summer solstice, then sinks but does not truly set until late September, at the autumn equinox.)

Imagine Earth as an apple sitting on one side of a table, with the stem being the North Pole. Tilt the apple 23.5 degrees so the stem points toward a candle (the sun) at the center of the table. That's summer for the top half of the apple.

Keep the stem pointing in the same direction but move the apple to the other side of the table: Now the stem points away from the candle, and it's winter on the top half of the fruit.

The very top of the apple, representing the north polar region, is in total darkness 24 hours a day, during that season.

At winter solstice, the sun arcs low across the Northern Hemisphere sky for those of us below the Arctic Circle, and the stretch of daylight is at its shortest. By the time of the spring equinox, days have grown noticeably longer.

At the summer solstice, the sun gets as high in our sky as it can go, yielding the longest day of the year in the Northern Hemisphere.

As long ago as the fourth century B.C., ancient peoples in the Americas understood enough of this that they could create giant calendars to interact with the cycle of sunlight. They built observatories of stone to mark the solstices and other times important for planting or harvesting crops. Shrines and even tombs were also designed with the sun in mind.

More seasonal facts

As we orbit the sun, the part of the night sky that's in our view changes. A given star sets about 4 minutes earlier each night. Over a month, this amounts to two hours.

In winter, this means that we're looking at stars that during the summer were in our daytime sky, overwhelmed of course by the glare of the sun. Since we complete a circle around the sun every year, the stars of summer, such as those in the Big Dipper, are always the stars of summer.

During summer on the top half of Earth, our planet is actually farther from the sun than during winter, a fact owing to our non-circular orbit around the sun. The difference is about 3 million miles (5 million kilometers), and it makes a difference in radiant heat received by the entire Earth of nearly 7 percent.

But the difference is more than made up for by the longer days in the Northern Hemisphere summer with the sun higher in the sky.

Which brings up a common question: If the summer solstice is the longest day of the year, why are the dog days of August typically hotter?

Because it takes a while for the oceans to warm up, and a lot of weather on land is driven by the heat of the oceans.

Tuesday, March 17, 2009

On St. Patrick's Day—Tuesday, March 17—millions of people will don green and celebrate the Irish in, and around, them with parades, good cheer, and perhaps a pint of beer.

But few St. Patrick's Day revelers have a clue about St. Patrick, the man, according to the author of St. Patrick of Ireland: A Biography.

"The modern celebration of St. Patrick's Day really has almost nothing to do with the real man," said classics professor Philip Freeman of Luther College in Iowa.

Who Was the Man Behind St. Patrick's Day?

The real St. Patrick wasn't even Irish.

He was born in Britain around the A.D. 390 to an aristocratic Christian family with a townhouse, a country villa, and plenty of slaves.

What's more, Patrick professed no interest in Christianity as a young boy, Freeman noted.

At 16, Patrick's world turned.

He was kidnapped and sent overseas to tend sheep as a slave in the chilly, mountainous countryside of Ireland for seven years.

"It was just horrible for him," Freeman said. "But he got a religious conversion while he was there and became a very deeply believing Christian."

Hearing Voices

According to folklore, a voice came to Patrick in his dreams, telling him to escape. He found passage on a pirate ship back to Britain, where he was reunited with his family.

The voice then told him to go back to Ireland.

"He gets ordained as a priest from a bishop and goes back and spends the rest of his life trying to convert the Irish to Christianity," Freeman said.

Patrick's work in Ireland was tough—he was constantly beaten by thugs, harassed by the Irish royalty, and admonished by his British superiors.

After he died on March 17, 461, Patrick was largely forgotten.

But slowly, mythology grew up around Patrick. Centuries later he was honored as the patron saint of Ireland, Freeman noted.

No Snakes in Ireland

The St. Patrick mythology includes the claim that he banished snakes from Ireland.

It's true no snakes exist on the island today, Freeman said. But they never did.

Ireland, after all, is surrounded by icy ocean waters—much too cold to allow snakes to migrate from Britain or anywhere else.

But since snakes often represent evil in literature, "when Patrick drives the snakes out of Ireland, it is symbolically saying he drove the old, evil, pagan ways out of Ireland [and] brought in a new age," Freeman said.

The snakes myth and others—such as Patrick using three-leafed shamrocks to explain the Holy Trinity (Father, Son, and Holy Ghost)—were likely spread by well-meaning monks centuries after St. Patrick's death, Freeman said.

St. Patrick's Day: Made in America?

Until the 1970s, St. Patrick's Day in Ireland was a minor religious holiday. A priest would acknowledge the feast day, and families would celebrate with a big meal, but that was about it.

"St. Patrick's Day was basically invented in America by Irish-Americans," Freeman said.

Timothy Meagher is an expert on Irish-American history at Catholic University in Washington, D.C.

He said Irish charitable organizations originally celebrated St. Patrick's Day with banquets in places such as Boston, Massachusetts; Savannah, Georgia; and Charleston, South Carolina.

Eighteenth-century Irish soldiers fighting with the British in the U.S. Revolutionary War held the first St. Patrick's Day parades. Some soldiers, for example, marched through New York City in 1762 to reconnect with their Irish roots.

Others parades followed in the years and decades after, including well-known celebrations in Boston, Philadelphia, and Chicago, primarily for flourishing Irish immigrant communities.

"It becomes a way to honor the saint but also to confirm ethnic identity and to create bonds of solidarity," Meagher said.

Wearing Green Clothes, Dyeing River Green

Sometime in the 19th century, as St. Patrick's Day parades were flourishing, wearing the color green became a show of commitment to Ireland, Meagher said.

In 1962 the show of solidarity took a spectacular turn in Chicago when the city decided to dye a portion of the Chicago River green.

The tradition started when parade organizer Steve Bailey, head of a plumbers' union, noticed how a dye used to detect river pollution had stained a colleague's overalls a brilliant green, according to greenchicagoriver.com.

Why not, Bailey thought, turn the river green on St. Patrick's Day? So began the tradition.

The environmental impact of the dye is minimal compared with sources of pollution such as bacteria from sewage-treatment plants, said Margaret Frisbie, the executive director of the advocacy group Friends of the Chicago River.

Her group focuses instead on turning the Chicago River into a well-known habitat full of fish, herons, turtles, and beavers.

If the river becomes a wildlife haven, the thinking goes, Chicagoans won't want to dye their river green.

"Our hope is that, as the river continues to improve, ultimately people can get excited about celebrating St. Patrick's Day different ways," she said.

Pint of Guinness

On any given day 5.5 million pints of Guinness, the famous Irish stout, are consumed around the world.

On St. Patrick's Day, that number more than doubles to 13 million pints, said Beth Davies Ryan, global corporate relations director of Guinness.

"Historically speaking, a lot of Irish immigrants came to the United States and brought with them lots of customs and traditions, one of them being Guinness," she said.

Today, the U.S. tradition of St. Patrick's Day parades, packed pubs, and green silliness has invaded Ireland with full force, noted Freeman, the classics professor.

The country, he noted, figured out the popularity of St. Patrick's Day was a good way to boost spring tourism.

"Like anybody else," he said, "they can take advantage of a good opportunity."

Wednesday, March 04, 2009

PENSACOLA, Fla. — Debbie Harris knew the military dog tag and small metal emblem of a Navy fighter squadron she recently found in the sand near her home on an Alabama beach belonged to a Blue Angels pilot who was killed when his jet crashed there a half-century ago.

But she wanted to find out more about Cmdr. Robert Nicholls Glasgow and what happened , so she turned to her aunt and uncle, who live in Pensacola, home of the National Museum of Naval Aviation. Their search led them to the museum's director, Bob Rasmussen, a retired Navy captain and once a member of the famed flight demonstration team.

"I said to myself, 'Isn't that a coincidence,' " Rasmussen mused. "Of all the people that they might have brought this to, it happened to be the person who was flying with him the morning he was killed in that crash."

That's not the only coincidence, Harris said Friday, when she went to the museum to show Rasmussen what she had found.

Harris, 56, of Fort Morgan, Ala., said she came upon the fire-scorched emblem from Fighter Squadron 191, one of Glasgow's previous units, in mid-October. It was nearly 50 years to the day after the Oct. 14, 1958 crash.

The emblem probably had been on a Zippo cigarette lighter, Rasmussen said. She also found a small piece of metal shaped like a W, but Rasmussen couldn't identify it.

Harris then found the dog tag, bent but with the pilot's name clearly visible, on Feb. 17 — Glasgow's birthday. He was born on that date in 1922.

"It's like he's — I don't know," Harris said. "It's spooky."

Harris thinks hurricanes that swept through the area in recent years may have uncovered the items.

She wants to give them to Glasgow's family, but she's been unable to find any relatives through her research on the Internet. An Oct. 15, 1958, article on the crash in the Pensacola News Journal indicated Glasgow had a wife and four children and that his parents lived in El Monte, Calif.

Rasmussen said he'll try to help her search, although he hardly knew Glasgow. Glasgow had reported for duty at Pensacola Naval Air Station as the Blue Angels new leader just a few days before his first flight in one of the team's F-11 Tigers ended in tragedy.

The outgoing Blue Angels commander, Ed Holley, had asked Rasmussen, one of the team's most experienced air show pilots, to take Glasgow on an orientation flight. They took off in separate jets on a clear, cloudless day and headed for the Blue Angels' practice area over the Gulf of Mexico just off the Alabama coast.

Rasmussen's No. 4 jet had just had its radio identification device replaced and he needed to fly to a higher altitude over Mobile, Ala., to test it, something Glasgow had been briefed on before they took off. Holley also told Rasmussen they could try some maneuvers at high altitude but nothing low.

"I dropped him off at the site and said, 'Just orbit here until I get back. I'll be back in three or four minutes,'" Rasmussen recalled.

It was their last communication.

"I went up there, checked out the equipment, came back on the radio, called him and he was already gone," Rasmussen said.

Rasmussen didn't see Glasgow's jet crash into a vacant house at Fort Morgan and then explode — only the aftermath.

"I could see the smoke and a big black mark on the beach," Rasmussen said. "Flying lower I could see some blue pieces of metal and it was pretty obvious what had happened."

Witnesses on the ground said the jet crashed while attempting a loop.

"I'm always looking for things there," said Harris, a retired aircraft company employee who works the night shift at a Wal-Mart. "I grew up knowing about the crash."

She said she found the squadron emblem no more than 200 feet from the crash site, now covered with sand and sea oats. She then did some research and found out the pilot's name before seeing it on the dog tag she spotted along a path between her house and the water.

"I was walking along there and looked down and I saw this and went, 'Um, oh my gosh,' " Harris said, her voice dropping to a whisper.

"It was like one of those magical moments," she said. "I stood there and the sun was setting and I held this in my hand and I said, 'No one has touched this since it was around his neck, and I'm touching it.' It was real emotional."